D2D communication is to perform terminal-to-terminal data communication without using a network (e.g., a cellular network) in order for a terminal to communicate with an adjacent terminal. In order for a terminal attempting D2D communication to discover an adjacent terminal of interest, the terminal may transmit and receive a message to and from the adjacent terminal or may receive assistance of a network. For example, a terminal attempting D2D communication may include information thereof in a discovery message and periodically transmit the discovery message. The adjacent terminal, having received the discovery message may recognize the existence of the terminal, having transmitted the discovery message through the information included in the discovery message. Such a method is referred to as an announce-monitoring mode. By the method, the terminal may discover a terminal of interest through a message transmitted from a terminal located at a periphery thereof.